Non-volatile memory devices including vertical nand channels and methods of forming the same

ABSTRACT

A non-volatile memory device can include a plurality of immediately adjacent offset vertical NAND channels that are electrically coupled to a single upper select gate line or to a single lower select gate line of the non-volatile memory device.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Korean Patent Application10-2009-0010546, filed on Feb. 10, 2009, in the Korean IntellectualProperty Office, the disclosure of which is incorporated by referenceherein in its entirety.

FIELD OF THE INVENTION

The present inventive concept relates to the field of semiconductors ingeneral, and more particularly, to method of forming semiconductordevices.

BACKGROUND

Vertical NAND channel configurations have been investigated to increasethe density of non-volatile memories. One such vertical NAND channelstructure is discussed in “Bit Cost Scalable Technology With Punch andPlug Process For Ultra High Density Flash Memory,” by H. Tanaka et al.in Symp. on VLSI Tech. Dig., pp 14˜15 (2007). Meanwhile, US PatentPublication No. 2009-0121271 entitled ‘Vertical-type non-volatile memorydevices’ discloses a vertical NAND having a metal gate and a method ofthe same. The disclosures of the above article and US publication areincorporated herein in their entirety.

SUMMARY

Embodiments according to the present invention can provide non-volatilememory devices including vertical NAND channels and methods of formingthe same. Pursuant to these embodiments, a non-volatile memory devicecan include a plurality of immediately adjacent offset vertical NANDchannels that are electrically coupled to a single upper select gateline or to a single lower select gate line of the non-volatile memorydevice. In other embodiment, a non-volatile memory device can include aplurality of immediately adjacent alternatingly offset vertical NANDchannels that are electrically coupled to a single upper select gateline or to a single lower select gate line of the non-volatile memorydevice. In another embodiment a non-volatile memory device can include aplurality of immediately adjacent vertical NAND channels that are offsetfrom one another in a bit line direction and that are electricallycoupled to a single upper select gate line or to a single lower selectgate line of the non-volatile memory device.

In some embodiments of the inventive concept, vertical NAND channels ofa nonvolatile memory device can be arranged in an offset way to moreclosely pack the vertical NAND channels within a respective upper orlower select gate line that is used to activate those channels. Forexample, immediately adjacent ones of the vertical NAND channels withina particular upper select gate line can be offset from one another inthe direction of the bit line that is connected to multiple upper selectgate lines.

The offset of the vertical NAND channels can increase the density of thememory cells within the upper select gate line. For example, the offsetin the bit line direction can allow the channels to be spaced closer toone another (in the upper select gate line direction) than would bepossible if the vertical NAND channels were to be fully aligned in theupper select gate line direction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are a plan view and a cross-sectional view,respectively, illustrating nonvolatile memory devices including verticalNAND channels wherein the vertical NAND channels are alternatinglyoffset from one another within respective upper/lower select gate linesin some embodiments of the inventive concept.

FIGS. 2A-2C are a plan view, a perspective view, and a perspectiveschematic view, respectively, illustrating offset vertical NAND channelscoupled to respective upper/lower select gate lines having two of everythree vertical NAND channels offset from one another in some embodimentsof the inventive concept.

FIGS. 3A-3E are a schematic plan view, a perspective view, a perspectiveschematic view, a plan view, and a cross-sectional view, respectively,illustrating offset vertical NAND channels within respective upper/lowergate lines symmetrically arranged to provide duplicates of one anotherin some embodiments of the inventive concept.

FIG. 4 is a schematic plan view illustrating offset vertical NANDchannels symmetrically arranged to provide a mirror arrangement of oneanother in some embodiments of the inventive concept.

FIGS. 5A-5D are a perspective view, a schematic perspective view, a planview, and a cross-sectional view, respectively, illustrating offsetvertical NAND channels with separate lower select gate lines paired withthe separate upper select gate lines in some embodiments of theinventive concept.

FIGS. 6A-6E are a schematic plan view, a perspective view, a schematicperspective view, a plan view and a cross-sectional view, respectively,illustrating alternatingly offset vertical NAND channels coupled toseparate upper select gate lines which are offset from one another in adirection of the vertical NAND channels in some embodiments of theinventive concept.

FIGS. 7A-7C are a schematic plan view, a perspective view, and a planview, respectively, illustrating alternatingly offset vertical NANDchannels which have been split (i.e., split channel) in some embodimentsof the inventive concept.

FIGS. 8A and 8B are a perspective view and a plan view, respectively,illustrating alternatingly offset vertical NAND channels being split(i.e., split channel) wherein the upper select gate lines are separatedfrom one another and are paired with similarly separated lower selectgate lines in some embodiments of the inventive concept.

FIGS. 9A-9C are a schematic plan view, a perspective view, and a planview, respectively, illustrating offset vertical NAND channels havingbeen split (i.e., split channel) coupled to interdigitated upper selectgate lines in some embodiments of the inventive concept.

FIGS. 10A-10B are a perspective view and a plan view, respectively,illustrating offset vertical NAND channels having been split (i.e.,split channel) coupled to separate upper select and lower select gatelines that are paired with one another and interdigitated in someembodiments of the inventive concept.

FIGS. 11A-11B are a schematic plan view, a perspective view, and a planview, respectively, illustrating alternatingly offset vertical NANDchannels having been split (i.e., split channel) coupled to separateupper and lower select gate lines paired with one another in someembodiments of the inventive concept.

FIG. 12 is a schematic representation of a standard form-factor memorycard including nonvolatile memory devices having offset vertical NANDchannels in some embodiments of the inventive concept.

FIG. 13 is a schematic representation of a system including anonvolatile memory system having offset vertical NAND channels in someembodiments of the inventive concept.

FIG. 14-23 are perspective views illustrating the formation ofnonvolatile memory devices including offset vertical NAND channels insome embodiments of the inventive concept.

FIGS. 24-29 are cross-sectional views illustrating the formation ofoffset vertical NAND channels in some embodiments of the inventiveconcept.

DETAILED DESCRIPTION OF EMBODIMENTS ACCORDING TO THE INVENTIVE CONCEPT

While the invention is susceptible to various modifications andalternative forms, specific embodiments thereof are shown by way ofexample in the drawings and will herein be described in detail. Itshould be understood, however, that there is no intent to limit theinvention to the particular forms disclosed, but on the contrary, theinvention is to cover all modifications, equivalents, and alternativesfalling within the spirit and scope of the invention as defined by theclaims.

The present invention now will be described more fully hereinafter withreference to the accompanying drawings, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art. In thedrawings, the size and relative sizes of layers and regions may beexaggerated for clarity. Like numbers refer to like elements throughout.

It will be understood that when an element such as a layer, region orsubstrate is referred to as being “on” or extending “onto” anotherelement, it can be directly on or extend directly onto the other elementor intervening elements may also be present. In contrast, when anelement is referred to as being “directly on” or extending “directlyonto” another element, there are no intervening elements present. Itwill also be understood that when an element is referred to as being“connected” or “coupled” to another element, it can be directlyconnected or coupled to the other element or intervening elements may bepresent. In contrast, when an element is referred to as being “directlyconnected” or “directly coupled” to another element, there are nointervening elements present.

Relative terms such as “below” or “above” or “upper” or “lower” or“horizontal” or “lateral” or “vertical” may be used herein to describe arelationship of one element, layer or region to another element, layeror region as illustrated in the figures. It will be understood thatthese terms are intended to encompass different orientations of thedevice in addition to the orientation depicted in the figures.

It will be understood that, although the terms first, second, etc. maybe used herein to describe various elements, components, regions, layersand/or sections, these elements, components, regions, layers and/orsections should not be limited by these terms. These teams are only usedto distinguish one element, component, region, layer or section fromanother region, layer or section. Thus, a first element, component,region, layer or section discussed below could be termed a secondelement, component, region, layer or section without departing from theteachings of the present invention.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms used herein should be interpreted ashaving a meaning that is consistent with their meaning in the context ofthis specification and the relevant art and will not be interpreted inan idealized or overly formal sense unless expressly so defined herein.

Embodiments of the invention are described herein with reference tocross-section illustrations that are schematic illustrations ofidealized embodiments (and intermediate structures) of the invention.The thickness of layers and regions in the drawings may be exaggeratedfor clarity. Additionally, variations from the shapes of theillustrations as a result, for example, of manufacturing techniquesand/or tolerances, are to be expected. Thus, embodiments of theinvention should not be construed as limited to the particular shapes ofregions illustrated herein but are to include deviations in shapes thatresult, for example, from manufacturing.

As described herein in greater detail, vertical NAND channels of anonvolatile memory device can be arranged in an offset way to moreclosely pack the vertical NAND channels within a respective upper orlower select gate line that is used to activate those channels. Forexample, immediately adjacent ones of the vertical NAND channels withina particular upper select gate line can be offset from one another inthe direction of the bit line that is connected to multiple upper selectgate lines. In this regard, the configuration including ‘an activeregion’ where a channel is formed, a tunnel insulation layer, a chargestorage layer, a block insulation layer and a conductive layer for acontrol gate is referred to as a ‘memory string’ or ‘string.’

The offset of the vertical NAND channels can increase the density of thememory cells within the upper select gate line. For example, the offsetin the bit line direction can allow the channels to be spaced closer toone another (in the upper select gate line direction) than would bepossible if the vertical NAND channels were to be fully aligned in theupper select gate line direction.

Furthermore, the offset of the immediately adjacent vertical NANDchannels can allow more channels to be activated by a single select gateline thereby increasing the page size and increasing the effectiveread/write performance of the device. In other words, increasing thepage size (by packing more vertical NAND channels onto a single upperselect gate line) can allow more data to be written to/read from thedevice during a single operation.

Further, many different patterns of the offset used for the immediatelyadjacent vertical NAND channels can be used to provide the advantagesdescribed above. For example, in some embodiments of the inventiveconcept, the plurality of immediately adjacent offset vertical NANDchannels provides that two of the vertical NAND channels are offset inthe bit line direction before the pattern repeats within the uppersselect gate line. In still further embodiments of the inventive concept,three vertical NAND channels are offset in a bit line direction beforethe pattern repeats. Still further, in other embodiments of theinventive concept, four vertical NAND channels can be offset in the bitline direction before the pattern repeats in the upper select gate line.Other repeating patterns can be use.

In still further embodiments of the inventive concept, the pattern usedto offset immediately adjacent ones of the vertical NAND channels can berepeated within an immediately adjacent upper select gate line toprovide duplicates of one another. In still further embodiments of theinventive concept, the pattern employed in one of the upper select gatelines is a mirror image of the pattern used in the immediately adjacentone of the upper select gate lines. In still other embodiments of theinventive concept, the offset vertical NAND channels can be configuredaccording to a random pattern.

In still further embodiments of the inventive concept, the offsetvertical NAND channels can be arranged within separate upper select gatelines which are paired with a single common lower select gate line. Instill further embodiments of the inventive concept, the offset verticalNAND channels are coupled to separate upper select gate lines which arepaired within respective separate lower select gate lines.

In still further embodiments of the inventive concept, immediatelyadjacent ones of the upper select gate lines (in which the offsetvertical NAND channels are deployed) are themselves offset from oneanother in a direction of the channels. In some embodiments of theinventive concept, the immediately adjacent offset vertical NANDchannels are deployed within a device wherein word lines used to programimmediately adjacent vertical NAND channels are separated from oneanother by an insulating material. In still further embodiments of theinventive concept, the word lines used to program immediately adjacentchannels are coupled to a common word line. In still further embodimentsof the inventive concept, the upper select gate lines employed with theoffset vertical NAND channels are interdigitated with one another. Infurther embodiments of the inventive concept, upper select gate linesused to activate immediately adjacent ones of the vertical NAND channelsare not interdigitated within one another.

FIGS. 1A and 1B are a schematic plan view and a cross-sectional view,respectively, illustrating a plurality of immediately adjacentalternatingly offset vertical NAND channels in some embodiments of theinventive concept. According to FIG. 1A, bit lines BL extend in adirection D to cross upper select gate lines USG1 and USG2 both of whichextend in a direction that is perpendicular to the direction D. Each ofthe bit lines BL is electrically connected to a single vertical NANDchannel PL within each of the upper select gate lines USG1 and USG2. Forexample, the bit line BL1 extends in the direction D across the upperselect gate line USG1 to electrically contact a first vertical NANDchannel PL1. The bit line BL continues in the direction D to cross overthe upper select gate line USG2 and to electrically contact a secondvertical NAND channel PL2.

As further shown in FIG. 1A, each of the upper select gate lines USG1and USG2 is electrically coupled to a plurality of the vertical NANDchannels PL, each of which is coupled to a respective bit line BL thatextends in the direction D. In some embodiments of the inventiveconcept, immediately adjacent ones of the vertical NAND channels PLconnected to the upper select gate lines USG1 and USG2 are alternatinglyoffset from one another in the direction D. In particular, the channelPL1 connected to USG1 is offset from the immediately adjacent channelPL3 in the direction D. Moreover, the immediately adjacent channel PL 4is also offset from the channel PL3. Therefore, it will be understoodthat the offset provided to each of the vertical NAND channelsalternates to provide a zig-zag or staggered pattern of vertical NANDchannels extending in the direction of the USG line USG1 which isperpendicular to the direction D.

Offsetting the immediately adjacent vertical NAND channels allows thosechannels to be more closely spaced to one another as the outer portionsof the vertical NAND channels are immediately adjacent to theneighboring bit line, rather than the neighboring channel as is found inmany conventional arrangements. As further shown in FIG. 1A, thisalternating offset provided to vertical NAND channels PL can be repeatedperiodically. For example, the channels PL coupled to upper select gateline USG1 are offset in an alternating fashion so that each of thechannels is offset from both of its immediate neighbors. Still further,this alternating pattern is repeated within upper select gate line USG1and upper select gate line USG2. The overall effect within thenonvolatile memory device is to increase the density of the verticalNAND channels thereby increasing the density of cells, and further,allowing the upper select gate line to contact more channels to therebyincrease the page size within the device. Increasing the page sizewithin the device can, in turn, increase the effective speed of thedevice by allowing more data to be read from or written to the devicesimultaneously.

As further shown in FIG. 1B, the vertical NAND channels PL (having awidth F) are arranged so the upper selected gate line USG is placedabove the cells that are controlled by the control gates (CG) whereasthe lower select gate line LSG is located beneath the cells controlledby the control gates.

It will be understood that in some embodiments of the inventive concept,offsetting vertical NAND channels in the bit line direction according tothe configuration described herein, can allow the channels to be spacedmore closely to the adjacent bit lines. For example, if a channel is ofa circular type including a pillar shape or a cylindrical type includingtubular type and bottomed cylindrical type viewed from the top and thewidth of a circle is labeled F, the effective area is defined as anaverage area for one channel to occupy on a top surface. Referring toFIG. 1A, the effective area for one channel will be reduced to 5 F² (=2F*5 F/2 channels) for a device of the present invention having arepeating pattern of two channels while 6 F² (=2 F*3 F/1 channel) for alayout of a conventional vertical NAND. For a device having a repeatingpattern of three channels, the required area is calculated as about 4.7F² (=2 F*7 F/3 channels) and for a device of four channels, the requiredarea is 4.5 F² (=2 F*9 F/4 channels), referring to FIG. 3A.

As such, integration of a device for example non-volatile devices suchas NAND is increased. According to the present invention, theprogramming and reading speed is also multiplied as the page size ismultiplied.

FIGS. 2A-2C are a schematic plan view, a perspective view, and aschematic perspective view of a plurality of immediately adjacent offsetvertical NAND channels in some embodiments of the inventive concept. Inparticular, FIG. 2A illustrates a configuration wherein vertical NANDchannels are offset from one another in the bit line direction D in arepeating pattern of three channels. In particular, the offset patternrepeats every third channel extending in the direction of the upperselect gate lines USG1 and USG2. In other words, whereas one of the rowsof channels may be considered to be aligned to one another, the othertwo channels within the pattern of three are offset from the initialchannel so that two of the three vertical channels are offset from thealigned channel.

As further illustrated in FIGS. 2A-2C, the pattern shown therein canincrease the density of cells (and the performance of the correspondingnonvolatile memory device) by increasing the number of channels withineach of the upper select gate lines. Still further, FIGS. 2A-2Cillustrate that the arrangements of immediately adjacent vertical NANDchannels provided in both of the upper select gate lines can besymmetrical to one another such that the arrangement shown in the upperselect gate line USG1 is a duplicate of that shown in upper select gateUSG2.

FIGS. 3A-3E are a schematic plan view, a perspective view, a schematicperspective view, a plan view and a cross-sectional view, respectively,that illustrate still further embodiments of the inventive conceptemploying offset vertical NAND channels. In particular, FIGS. 3A-3E showan arrangement of four vertical NAND channels in an offset arrangement.As further shown in FIGS. 3A-3E, the separate upper select gate linesUSG1 and USG2 are paired with a single common lower select gate lineLSG.

Furthermore, the arrangements shown within the upper select gate lineUSG1 and the upper select gate line USG2 are symmetrical so that each isa duplicate of the other. Still further, the region A is FIG. 3Aillustrates that the offset applied to the immediately adjacent NANDchannels can increase the density of the cells so that the four cellsshown within the region A can effectively be packed into about 4 and ahalf of a standard channel (equal to 4.5 F² of effective area), whichrepresents an increase in density compared to some conventionalapproaches.

FIG. 4 is a schematic plan view of a plurality of immediately adjacentand offset vertical NAND channels according to some embodiments of thepresent invention. An arrangement shown in FIG. 4 utilizes a pattern offour channels that are offset from one another. In particular, channelsPL1-PL4 shown coupled to upper select gate line USG 1 are each offsetfrom one another in the bit line direction D. Furthermore, this patternrepeats in the direction which is perpendicular to the bit linedirection D. Still further, the arrangements in the upper select gateline USG 1 and the upper select gate line USG 2 are mirror images of oneanother relative to the reference line M.

FIGS. 5A-5D are a perspective view, a schematic perspective view, a planview, and a cross-sectional view, respectively, that illustrate theplurality of immediately adjacent offset NAND channels arranged withinseparate upper select gate lines paired with similarly separated lowerselect gate lines in some embodiments of the inventive concept andanalogous to that described above in relation to FIGS. 3A-3E. However,FIGS. 5A-5D show that the plurality of offset vertical NAND channels PLare coupled to respective ones of the separate upper select gate linesUSG1 and USG2 and, further, that each of those upper select gate linesUSG 1 and 2 is paired with a separate lower select gate line LSG1 andLSG2.

FIGS. 6A-6E are a schematic plan view, a perspective view, a schematicperspective view, a plan view and a cross-sectional view, respectively,illustrating immediately adjacent alternatingly offset vertical NANDchannels coupled to upper select gate lines that are offset from oneanother in some embodiments of the inventive concept. In particular,FIGS. 6A-6E show an upper select gate line USG1, USG3 . . . immediatelyadjacent to a second upper select gate line USG2, USG4 . . . . The bitlines BL extend across the upper select gate lines USG1 and USG2 in thedirection D to electrically contact the channels PL. It will beunderstood that the upper select gate lines USG1 and USG2 are offsetfrom one another in a direction of the vertical channels PL. Forexample, as shown in FIG. 6B, the upper select gate line USG1 is shownabove the upper select gate line USG2. Accordingly, in some embodimentsof the inventive concept, in addition to the plurality of immediatelyadjacent vertical NAND channels being alternatingly offset, the upperselect gate lines used to activate those channels can also be offsetfrom one another in the direction of the channels in some embodiments ofthe inventive concept.

FIGS. 7A-7C are a schematic plan view, a perspective view, and a planview, respectively, illustrating immediately adjacent alternatinglyoffset vertical NAND channels having been split in some embodiments ofthe inventive concept. In particular, as shown in FIG. 7A, the splitchannels can be provided by separating what would otherwise be formed asa single channel PLS into two separate channels which are insulated fromone another. As in FIG. 1-6 that vertical channel where the channel willbe formed is of a pillar or tubular shape, USG or LSG surrounds thevertical channel. In contrast, for FIG. 7A-7C where vertical channel isof split type and separated split channels face each other, splitchannels should be connected to other USG or LSG because they areconnected to the same bit line and word line. Thus, in operation, theupper select gate lines which contact the NAND channel split channelsoperate independently of one another. For example, as shown in FIG. 7B,the split channels PL are formed in what would otherwise be a singlechannel as shown, for example, above in FIG. 5A. Moreover, separateupper select gate lines USG 1-4 can electrically contact each of thesplit channels so that each may be operating independently. For example,USG1 is shown electrically coupled to one side of the split channel PLwhereas upper select gate line USG2 is shown coupled to the opposingside of the split channel PL. Still further, the lower select gate lineLSG can be provided in common with each of the separate upper selectgate lines.

FIGS. 8A-8B are a perspective view and a plan view illustratingimmediately adjacent alternatingly offset vertical NAND channel splitchannels with separate lower select gate lines paired with the separateupper gate select lines in some embodiments of the inventive concept.For example, as shown in FIG. 8A, upper select gate line USG1 is coupledto one side of the split channel PL whereas the second upper select gateline USG2 is coupled to the opposite side of the split channel.Moreover, the lower select gate line 1 is paired with the upper selectgate line USG1 and the lower select gate line LSG2 is paired with theupper select gate line USG2. Accordingly, separate lower select gatelines can be paired with separate upper select gate lines in someembodiments of the inventive concept. This embodiment may be applied tothe device disclosed in “Bit Cost Scalable Technology With Punch andPlug Process For Ultra High Density Flash Memory,” by H. Tanaka et al.in Symp. On VLSI Tech. Dig., pp 14-15 (2007).

FIGS. 9A-9C are a schematic plan view, a perspective view, and a planview, respectively, illustrating immediately adjacent offset verticalNAND channel split channels having interdigitated upper select gatelines in some embodiments of the inventive concept. For example, asshown in FIG. 9A, opposing sides PL1 and PL2 of the split channel whichwould otherwise be part of a single channel PLS are coupled to differentupper select gate lines USG1 and USG2. Moreover, the upper select gatelines USG1 and USG3 (electrically coupled to one another) areinterdigitated with the upper select gate line USG2 so that at least aportion of the upper select gate line USG2 extends inside an openingthat is defined by the layout of the upper select gate lines USG1 andUSG3. Similarly, the upper select gate line USG3 is interdigitated withthe upper select gate lines USG2 and USG4 so that at least a portion ofthe upper select gate line USG3 extends inside an opening that isdefined by the layout of the upper select gate lines USG2 and USG4.Accordingly, immediately adjacent split channels PL formed fromdifferent channels PLS are electrically coupled to different upperselect gate lines. Furthermore, the separate upper select gate lines canbe paired with a common lower select gate line LSG1 as shown, forexample, in FIG. 9B.

FIGS. 10A-10B are a perspective view and a plan view, respectively,illustrating a plurality of immediately adjacent offset vertical NANDchannel split channels coupled to interdigitated upper selected gatelines which are paired with similarly separated interdigitated lowerselect gate lines LSG in some embodiments of the inventive concept.

FIGS. 11A-11B are a schematic plan view and a perspective view,respectively, illustrating a plurality of immediately adjacentalternatingly offset vertical NAND channel split channels coupled tonon-interdigitated upper select gate lines in some embodiments of theinventive concept. In particular, as shown in FIG. 11A, split channelsfoamed from different pillars and immediately adjacent to one anotherare electrically coupled to upper select gate lines which are coupledtogether. In particular, FIG. 11A shows that, for example, upper selectgate USG2 is electrically connected to a first plurality of splitchannels PL1 whereas upper select gate line 3 is electrically connectedto a separate plurality of split channels PL2 which are adjacent to thefirst plurality of split channels. Moreover, the first and secondpluralities of split channels PL1 and PL2 are associated with differentpillars PLS 1 and PLS 2 used to form the split channels. Further, theupper select gate line USG2 is electrically connected to the upperselect gate line USG3. Overall, the upper select gate lines, which areconnected together to contact immediately adjacent ones of the splitchannels, are not interdigitated with one another in contrast to thearrangement shown, for example, in FIGS. 10A-10B in some embodiments ofthe inventive concept. The manner of electrically connecting USG2 andUSG3 is not limited and varied according to the inventive concept of thepresent invention. For example, USG 2 and USG3 may be patterned to forma line. Alternatively, they can be connected by means of other extensionsuch as ‘via.’ This embodiment may be applied to the device disclosed inUS Patent Publication No. 2009-0121271 entitled ‘Vertical-typenon-volatile memory devices, wherein a further trench for separatingmetal gate is required.

FIG. 12 is a schematic representation of a standard form-factor memorycard 10 that can include nonvolatile memory devices includingimmediately adjacent offset vertical NAND channels (either split ornonsplit) in some embodiments of the inventive concept. In operation,the standard form-factor memory card 10 can provide data pins 13 alongan edge thereof so that data may be provided to/from the card. Stillfurther, a processor circuit 11 can coordinate operation of the memorycard 10 so data provided to the memory card 10 is stored within anonvolatile memory 12 by issuing data and commands thereto. Stillfurther, the processor circuit 11 can issue commands to the nonvolatilememory 12 to retrieve requested data which is then, in turn, providedfrom the memory card 10 via the data pins 13 in some embodiments of theinventive concept.

It will be understood that a memory card can be a Multi-Media Card(MMC)/Secure Digital (SD) form-factor compliant memory card. As usedherein, the term “form-factor” means the physical size and shape of thememory card. Moreover, the form-factor of memory cards according to someembodiments of the invention is described herein as a Multi-Media Card(MMC)/Secure Digital memory card that has a size and shape that allowssuch memory cards to be used with other compliant devices, such asreaders. As known to those skilled in the art, SD represents a laterdeveloped version of the MMC standard which may allow MMC compliantmemory cards to be used with SD compliant devices. In some embodimentsof the inventive concept, MMC/SD form-factor compliant devices measureabout 32 mm×about 24 mm×about 1.4 mm and can be shaped substantially asshown in FIG. 12. The MMC and SD standards are discussed further on theworld-wide-web at “mmca.org.”

FIG. 13 is a schematic illustration of a system 20 including anonvolatile memory 22 including immediately adjacent offset verticalNAND channels (either split or nonsplit) in some embodiments of theinventive concept. In particular, a processor circuit 21 can interactwith various subcomponents of the system 20 via a bus 24 to, forexample, provide data from the system 20 via an I/O subsystem 23 whichreceive data from outside the system 20. Still further, the processorcircuit 21 can provide data to/from the nonvolatile memory 22 via thebus 24 to, for example, store data therein or to retrieve datatherefrom. The data may either be provided via the I/O subsystem 23 fromoutside or may be fetched from the nonvolatile memory 22 and providedexternal to the system 20 via the I/O subsystem 23 under processorcircuit 21 control. It will be understood that the nonvolatile memory 22can include nonvolatile memory devices including immediately adjacentoffset vertical NAND channels (either split or nonsplit) in someembodiments of the inventive concept.

The vertical NAND devices having a plurality of immediate adjacentoffset vertical channels according to the present invention increasespage size thereby increasing read/write performance of the devices.Referring to FIG. 2C wherein CG and LSG are common for channels,exemplified voltage values that can be applied to a bit line, upperselection gate (USG) and so on are indicated in the table below. In thetable, Vcc means a ‘turn on voltage’ for USG, Vpass means a ‘passvoltage’ for lessening Program disturbance, Vpgm a ‘programmingvoltage’, Verase an erase voltage, Vread_pass, a ‘read pass voltage’applied to unselected control gate, Vread a ‘read,’ applied to selectedcontrol gate, respectively. ‘Floating’ means that the correspondingelement is floated to a certain voltage without applying any voltage.The operation of the vertical NAND devices is more described in USPatent Publication No. 2009-0310425 entitled. “Memory Devices IncludingVertical Pillars And Methods Of Manufacturing And Operating The Same,”the disclosure of which is hereby incorporated herein by reference.

Erase Device in FIG. 29 Device in FIG. 23 Program (GIDL type) (Body-tiedtype) Read Selected BL 0 Vcc floating 0.5~1 V Unselected BL Vcc VccFloating 0 V Selected USG Vcc Verase Floating Vread_pass Unselected USG0 V Verase Floating 0 V Unselected CG Vpass 0~1 V 0~1 V Vread_passSelected CG Vpgm 0~1 V 0~1 V Vread LSG 0 V Verase Floating Vread_passCSL (not shown) 1.5 V Verase Floating 0 V PPW (not shown) 0 V VeraseVerase 0 V

FIGS. 14-24 are perspective views illustrating the formation of anonvolatile memory device including immediately adjacent alternatinglyoffset vertical NAND channel channels in some embodiments of theinventive concept.

According to FIG. 14, an alternating stack of layers 1400 is formedwhich may be ultimately used for the formation of the different featuresshown to provide the nonvolatile memory devices including the pluralityof the immediately adjacent alternatingly offset vertical NAND channelsin some embodiments of the inventive concept. According to FIG. 15, thestack of layers 1400 is selectively patterned and remove portionsthereof to form contacts 1501 and 1502 where channels will ultimately beformed for the nonvolatile memory. The shape of mask for patterning ismanufactured so that the contacts are of an offset form in thisembodiment. According to FIG. 16, materials are formed in the recessesto ultimately provide the split channels described herein. For example,the materials are silicon for an active region with a pillar shape ortubular shape. In case of an active region of tubular shape, therecessed portion may be filled with insulating layer such as siliconoxide.

According to FIG. 17, a region between the channels is removed to form arecess 1700 so that portions of the stacked layers 1400 where the wordlines (control gates) will ultimately be formed can be accessed.According to FIG. 18, a number of the stacked layers 1400 (such as thoseformed of SiN) can be selectively removed so that lateral recesses 1800are provided wherein control gate structures, for example control gateof metal, will ultimately be formed. According to FIG. 19, multiplelayers (such as a tunnel layer, a charge storage layer, and a blockingoxide film) are sequentially formed within the lateral recesses 1800where the control gates will ultimately be formed. According to FIG. 20,a gate metal material 2000 is deposited in the recess 1700 between thechannels as well as within the remaining voids left in the lateralrecesses 1800. The gate metal material can be deposited fully or inportion so that the material can sufficiently fill lateral recess 1800.According to FIG. 21, a portion of the gate metal material 2000 isremoved from the recess 1700 between adjacent channels to separateelectrically the gate metal material 2000 which was deposited in thelateral recesses 1800.

According to FIG. 22, an isolation material 2200 is deposited in therecess 1700 between the channels so that the control gates used tocontrol immediately adjacent ones of the channels can be isolated fromone another. According to FIG. 23, etching is performed to removeportions of the stacked layers 1400 to create separate split channels2300 to provide the plurality of immediately adjacent alternatinglyoffset vertical NAND channel split channels in some embodiments of theinventive concept. According to FIG. 24, after forming USG on thechannels and electrically connecting USG to channels, bit lines 2400 areformed extending across the channels. It will be understood that theformation of the upper select gate lines between the bit lines and thechannels is not shown for simplicity.

FIGS. 24-29 are cross-sectional views that illustrate the formation ofnonvolatile memory devices including a plurality of immediately adjacentalternatingly offset vertical NAND channels in some embodiments of theinventive concept. In particular, FIGS. 24-29 illustrate the formationof nonvolatile memory devices wherein control gates used to controlimmediately adjacent ones of the channels are not separated by aninsulating material in contrast to that described above in reference toFIGS. 14-23.

According to FIG. 24, an alternating stack of layers 2500 is formedsimilar to that described above in reference to FIG. 14. In contrast tothe embodiments depicted in FIG. 14-23, the stack 2500 is comprised ofconductive layers such as silicon and insulating layers such as siliconoxide. According to FIG. 25, portions of the stacked layers 1400 areremoved to provide contacts 2600 in an offset pattern wherein thechannels will ultimately be formed. According to FIG. 26, multiplelayers 2700 are formed in the contacts 2600 to provide the layersbetween the control gates and the channel material which is formed inthe contact.

According to FIG. 27, heavy doping is provided to a layer 2800 formedabove the vertical NAND channels to provide the bases for the upperselect gate lines. According to FIG. 28, the upper layers 2900 of thestack are patterned to separate the upper select gate lines from oneanother so that they may independently control the separate channels.According to FIG. 29, the bit lines are then formed over the channelselect lines and extend in a direction which is perpendicular thereto.As shown in FIG. 29, immediately adjacent ones of the vertical NANDchannels are controlled by control gates defined by the alternatingstacked layers 2500 which are not separated from one another. In otherwords, immediately adjacent ones of the channels 3000 are controlled bycontrol gates within the stacked layers 2500 which extend between andconnect to the immediately adjacent ones of the channels 300 and aretherefore, not separated by an insulating material.

As described herein in greater detail, vertical NAND channels of anonvolatile memory device can be arranged in an offset way to moreclosely pack the vertical NAND channels within a respective upper orlower select gate line that is used to activate those channels. Forexample, immediately adjacent ones of the vertical NAND channels withina particular upper select gate line can be offset from one another inthe direction of the bit line that is connected to multiple upper selectgate lines.

The offset of the vertical NAND channels can increase the density of thechannels within the upper select gate line. For example, the offset inthe bit line direction can allow the channels to be spaced closer to oneanother (in the upper select gate line direction) than would be possibleif the vertical NAND channels were to be fully aligned in the upperselect gate line direction.

Furthermore, the offset of the immediately adjacent vertical NANDchannels can allow more channels to be activated by a single select gateline thereby increasing the page size and increasing the effectiveread/write performance of the device. In other words, increasing thepage size (by packing more vertical NAND channels onto a single upperselect gate line) can allow more data to be written to/read from thedevice during a single operation.

Further, many different patterns of the offset used for the immediatelyadjacent vertical NAND channels can be used to provide the advantagesdescribed above. For example, in some embodiments of the inventiveconcept, the plurality of immediately adjacent offset vertical NANDchannels provides that two of the vertical NAND channels are offset inthe bit line direction before the pattern repeats within the uppersselect gate line. In still further embodiments of the inventive concept,three vertical NAND channels are offset in a bit line direction beforethe pattern repeats. Still further, in other embodiments of theinventive concept, four vertical NAND channels can be offset in the bitline direction before the pattern repeats in the upper select gate line.Other repeating patterns can be use.

In still further embodiments of the inventive concept, the pattern usedto offset immediately adjacent ones of the vertical NAND channels can berepeated within immediately adjacent upper select gate line to provideduplicates of one another. In still further embodiments of the inventiveconcept, the pattern employed in one of the upper select gate lines is amirror image of the pattern used in the immediately adjacent one of theupper select gate lines. In still other embodiments of the inventiveconcept, the offset vertical NAND channels can be configured accordingto a random pattern.

In still further embodiments of the inventive concept, the offsetvertical NAND channels can be arranged within separate upper select gatelines which are paired with a single common lower select gate line. Instill further embodiments of the inventive concept, the offset verticalNAND channels are coupled to separate upper select gate lines which arepaired within respective separate lower select gate lines.

In still further embodiments of the inventive concept, immediatelyadjacent ones of the upper select gate lines (in which the offsetvertical NAND channels are deployed) are themselves offset from oneanother in a direction of the channels. In some embodiments of theinventive concept, the immediately adjacent offset vertical NANDchannels are deployed within a device wherein word lines used to programimmediately adjacent vertical NAND channels are separated from oneanother by an insulating material. In still further embodiments of theinventive concept, the word lines used to program immediately adjacentchannels are coupled to a common word line. In still further embodimentsof the inventive concept, the upper select gate lines employed with theoffset vertical NAND channels are interdigitated with one another. Infurther embodiments of the inventive concept, upper select gate linesused to activate immediately adjacent ones of the vertical NAND channelsare not interdigitated within one another.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the invention. Thus, it isintended that the invention covers the modifications and variations ofthis invention provided they come within the scope of the appendedclaims and their equivalents.

1. A non-volatile memory device comprising: a plurality of immediatelyadjacent offset vertical NAND channels electrically coupled to a singleselect gate line of the non-volatile memory device.
 2. A deviceaccording to claim 1, wherein the plurality of immediately adjacentoffset vertical NAND channels are offset from one another in a bit linedirection defined in the non-volatile memory device.
 3. A deviceaccording to claim 2, wherein the plurality of immediately adjacentoffset vertical NAND channels are offset in a direction perpendicular tothe bit line direction by a distance less than about twice a width of asingle channel included in the plurality of immediately adjacent offsetvertical NAND channels.
 4. A device according to claim 3 wherein thedistance is measured from a center of a bit line to a center of one theplurality of immediately adjacent offset vertical NAND channelselectrically coupled to an immediately adjacent bit line.
 5. A deviceaccording to claim 1 wherein separate pluralities of immediatelyadjacent offset vertical NAND channels electrically coupled toimmediately adjacent select gate lines are symmetrically arrangedrelative to one another.
 6. A device according to claim 1 whereinseparate pluralities of immediately adjacent offset vertical NANDchannels electrically coupled to immediately adjacent select gate linesare symmetrically arranged as a mirror image of one another.
 7. A deviceaccording to claim 1 wherein separate pluralities of immediatelyadjacent offset vertical NAND channels electrically coupled toimmediately adjacent select gate lines are symmetrically arranged asduplicates of one another.
 8. A device according to claim 1 whereinseparate pluralities of immediately adjacent offset vertical NANDchannels electrically coupled to immediately adjacent select gate linesare randomly arranged relative to one another.
 9. A device according toclaim 1 further comprising: immediately adjacent upper or lower selectgate lines coupled to respective separate pluralities of immediatelyadjacent offset vertical NAND channels, wherein the immediately adjacentselect gate lines are offset relative to one another in a direction ofthe pluralities of immediately adjacent offset vertical NAND channels.10. A device according to claim 1 wherein immediately adjacent bit linescoupled to the immediately adjacent offset vertical NAND channels arenarrower than a width of the channels.
 11. A device according to claim 1wherein the immediately adjacent offset vertical NAND channels arelogically arranged to provide activate a single page of the non-volatilememory device.
 12. A device according to claim 2, wherein the pluralityof immediately adjacent offset vertical NAND channels comprises a firstchannel, a second channel offset from the first channel, a third channeloffset from the first and second channels, and a fourth channel alignedto the first channel in a direction perpendicular to the bit linedirection.
 13. A device according to claim 2, wherein the plurality ofimmediately adjacent offset vertical NAND channels comprises a firstchannel, a second channel offset from the first channel, a third channeloffset from the first and second channels, a fourth channel offset fromthe first, second and third channels, and a fifth channel aligned to thefirst channel in a direction perpendicular to the bit line direction.14. A device according to claim 2, wherein the plurality of immediatelyadjacent offset vertical NAND channels comprises a first channel, asecond channel offset from the first channel, a third channel offsetfrom the first and second channels, a fourth channel offset from thefirst, second and third channels, a fifth channel offset from the first,second, third channel, and fourth channels, and a sixth channel alignedto the first channel in a direction perpendicular to the bit linedirection.
 15. A device according to claim 1 wherein the channelscomprise either a pillar or cylindrically shaped channel.
 16. A deviceaccording to claim 1 wherein the plurality of immediately adjacentoffset vertical NAND channels electrically coupled to a single upperselect gate line of the non-volatile memory device.
 17. A deviceaccording to claim 1 wherein the channels comprise split channels.
 18. Adevice according to claim 1 wherein the lower select gate line iscoupled to each of the vertical channels.
 19. A device according toclaim 1 further comprising: a plurality of control gates coupled torespective ones of the channels; a plurality or word lines electricallycoupled to the plurality of control gates, wherein immediately adjacentones of the plurality of word lines are electrically connected to oneanother.
 20. A device according to claim 1 further comprising: aplurality of control gates coupled to respective ones of the channels; aplurality or word lines electrically coupled to the plurality of controlgates; and an electrically insulating layer separating immediatelyadjacent ones of the plurality of word lines from one another.
 21. Aplurality of vertical NAND channels electrically coupled to a singleupper or lower select gate line, wherein immediately adjacent ones ofthe plurality of channels are offset from one another in a directionperpendicular to a direction in which a bit line extends.
 22. Anon-volatile memory device comprising: a plurality of adjacent verticalNAND channels arranged in a repeating staggered pattern extending in adirection perpendicular to a bit line direction and electrically coupledto a single upper select gate line or single lower select gate line ofthe non-volatile memory device.
 23. A non-volatile memory devicecomprising: a plurality of vertical NAND channels arranged in a zig-zagpattern defined to include immediately adjacent ones of the channelswithin a single logical page of the device.
 24. A device according toclaim 23, wherein the NAND channels are selected using a single upperselect gate line of the non-volatile memory device.
 25. A vertical NANDmemory device comprising: A substrate; and a plurality of immediatelyadjacent offset vertical NAND channels electrically coupled to a singleselect gate line of the vertical NAND device and extending upwardly fromthe substrate, Wherein provided that a channel is of a circular orcylindrical type and the width of the channel is labeled F, theeffective area for one channel viewed from the top is not less than 4 F²and less than 6 F².